Case IH 3626 – Engine Control Module (ECM) / EDC (Electronic Diesel Control): Crank case pressure sensor not plausible

The engine control unit has detected that the signal coming from the crankcase pressure sensor is outside of the expected physical range or does not align with current engine operating conditions. This can be triggered by a failed sensor, a wiring issue (such as a short circuit), or a genuine excessive crankcase pressure condition (blow-by) caused by a clogged crankcase breather filter or internal engine wear.

• Steiger
• Magnum
• Puma
• Farmall
• Axial-Flow 5140
• Axial-Flow 6140
• Axial-Flow 7140
• Axial-Flow 7240
• Axial-Flow 8240
• Axial-Flow 9240

1. 1

   Check the engine oil level to ensure it is not overfilled. Fuel-in-oil dilution can raise the oil level and artificially increase crankcase pressure.

2. 2

   Inspect the crankcase breather / blow-by filter. A plugged blow-by filter is a primary mechanical cause of high crankcase pressure.

3. 3

   Inspect the 3-pin connector and the wiring harness leading to the crankcase pressure sensor for chafing, corrosion, or a short-to-voltage.

4. 4

   Use the CNH Electronic Service Tool (EST) to monitor the live voltage of the crankcase pressure sensor. If the voltage is pegged at the upper limit even when the engine is off, the sensor or wiring is faulty.

1. 1

   Preparation

   Turn off the machine, remove the key, and allow the engine to cool.

2. 2

   Locate the Sensor

   Locate the crankcase pressure sensor on the engine block. It is typically mounted near the crankcase breather/blow-by filter assembly.

3. 3

   Disconnect

   Depress the locking tab on the 3-pin electrical connector and unplug it from the sensor.

4. 4

   Removal

   Unbolt or unscrew the faulty pressure sensor from its mounting port. Be prepared with a rag to catch any residual oil drips.

5. 5

   Installation

   Install the new OEM crankcase pressure sensor and tighten it to the engine manufacturer's specified torque.

6. 6

   Reassembly

   Reconnect the electrical harness, ensuring it clicks securely into place.

7. 7

   Filter Replacement (Highly Recommended)

   If it has not been done recently, replace the crankcase blow-by filter element to ensure the new sensor isn't subjected to excessive pressure.

8. 8

   Clear Codes

   Turn the ignition on and use a diagnostic tool to clear the inactive 3626 fault code. Start the engine and verify that the code does not return.